When this occurs it is likely that the Polycom configuration files require an update to define 'Push-to-Talk' or Auto Answer behavior. By default this behavior is not defined by Poloycom and will need to be added to the 'sip.cfg' configuration file.

Typically, all Polycom phones will retrieve their configuration files from a TFTP server located by each phone on boot up via DHCP options 66 or 150. It is on this server where you will need to make modifications to the 'sip.cfg' configuration file. Since the 'sip.cfg' file name is customizable you may need to ask the Polycom phone administrator for its location and then possibly request the following changes are made.

The first step is to identify the 'Push-To-Talk' trigger method being used by the WARP Pager. By default the WARP Pager will use 'Ring Answer' unless overridden in its configuration file. In the file <WARP Pager MAC Address>.cfg (eg. 001e840000ce.cfg), used to provision the unit, there is an optional parameter called 'answer_string'. If not present then the 'Ring Answer' string is used as default but when present the associated string is used to create the 'Alert-Info:<STRING>' SIP header (eg. Alert-Info: Ring Answer) that is added to each 'Page' INVITE request. We need to configure the Polycom phones to recognize this trigger and assign 'Push-To-Talk' behavior when recognized.

In the 'sip.cfg' file we will need to add an 'alertInfo' XML tag to define 'Ring Answer'. This tag will be nested in the 'SIP' XML tag and will look as follows:

In this example 'alertInfo' index '1' (eg. 'voIpProt.SIP.alertInfo.1') is being used. If already defined in your file just increment to next available index value. The tag tells a Polycom phone to use 'ringType' class index '4' as a ring type behavioral definition when recognized.

We will now define the 'ringType' behavior further down in the 'sip.cfg' configuration file. Below you will see a 'ringType' XML tag where we will define the 'Ring Answer' functional behavior. We will add a nested 'RING_ANSWER' XML tag like so:

This example uses ring type class 4 which may not be available in your configuration file. If this is the case then increment this value to the next available number. Note: The previous 'alertInfo' XML Tags class value ( voIpProt.SIP.alertInfo.1.class="4") needs to match what is defined here. The 'RING_ANSWER' ring type will play a short burst of tone of type 'ringer=2' and then auto-answer the incoming call.

Here is an example 'sip.cfg' file that contains the changes outlined above:

ftp://ftp.pikatech.com/outgoing/Polycom-Sip-Cfg/

I used a default 3.1 version sip.cfg file and also add a copy of the SoundPoint IP Administrator's Guide for your reference.

Once these changes are in place save the file on the Polycom's configuration TFTP server. Once done all associated Polycom Phones will require a reboot to upload the latest changes.

When all phones have rebooted they will Auto-Answer the next Page made by the WARP Pager.